Transmitting apparatus.



H. SHOBMAKER.

TRANSMITTING APPARATUS.

ArimoA'non FILED JULY 22, 190B.

927,433. Patented July 6, 1909.

WITNESSES: I INVENTOR fimJMW "5 y' M) SW M-251$J- 16 xrronnar IO--01 other transmitter,

those am 1 heremafter pointed out and claimed.

HARRY SHOEMAKER, OF JERSEY CITY, NEW JERSEY.

TRAN MITTING APPARATUS.

Specification of Letters Patent.

Patented July 6, 1909.

Application filed July 22, 1908. Serial No. 444,781.

To all whom it may concern:

Be it known that I, HARRY SHOEMAKER, a citizen of the United States, residing in Jersey City, county of Hudson, State of New 5 Jersey, have invented certain new and useful provcments in Transmitting Apparatus,

of which the .following is a specification.

M --invention relates to the control of electrica energy, particularly by a telegraph key and more especially when used in connection with alternating currents, as in a wireless or other signaling system.

It isthe object of my invention to control electrical energy, particularly when in the i alternating current form, as used in the transmitting apparatus of a wireless telegraph or other system, where the amount of energy to be controlled is relatively great and yet to be controlled bya key or other transmitter operated to represent dots and dashes or other characters. To this end, I provide difl'erential inductances, which are arranged preferably as shown in the accompanying drawing,

- one or more of the inductive windings bein always in circuit while the key, when close .throws into circuit windings in differential relation to that or permanently in circuit. My Invention resides also in other features For an illustration of two of the forms my vention may take reference is to be had to the accompanying drawing, in which: 36* Figure 1 is adiagrammatic view of a wireless telegraph transmitter, involving my invention. 'g. 2 is a diagrammatic view illustrating a modified arrangement.

' Referring to Fig. l, G is a source or enera- 46- 01 of electrical energy, preferably ternating current energy. Connected in circuit such source is apriniaup' P of a step-u transformer a justah einductance and also an adjustable inductive winding L 'dispoeed u on a laminated or other suitable ma etiza le core C. Connected in shunt to able inductive winding Land the switch or tel phicktiy or'other transmitter k. The 50 will k sistence inductance, an referably of conductors of the same sfizeand oftthe same number-of turns, both windings 'Demg disposed about the core 0, but difierentially wound or connected. The secondary S, of

one or more inductive e adjustableinductance L is the adj ust-.

are preferabl' similar in rethe transformer T, is bridged by the condensers K and these by a spar gap 8 and the adjustahle inductance I. A is the aerial conductor, of any suitable form, of a wireless telegraph transmitting station, between which and the earth connection E is connected a variable portion of the inductance I. The inductive L is always in circuit with the generator G and the primary P and the value of the current flowing in the circuit will depend upon the inductance of such winding L to etherwith other factors of the circuit, and t is current value may be made anything desired. When the key 7: is depressed, current will also flow through the inductive windin L" but since these coils are in differential re ation with res ect to each other, and if they are substantia y similar in magnetizing effects, the magnetizing eflect upon the core C becomes practically zero, and the value of the combined self-induction of the two coils, L and L', is reduced to practically zero and, in consequence, a very much greater current will flow through the primary P. And, as well known, the seconda S charges the condensers K, K and they ischarge through the spark gap 8 and the inductance I at 'gh fre uency, as well understood in the art of e ectromagnetic waves, causing electro-radiant energy toje radiated from the aerial conductor A an trains, groups or amounts to represent characters. In practice, it is preferable to have the two coils L and L adjustable so as to secure any desired effect. It is to be understood, however, that the coils L, L may be dissimilar in inductive eflect, turns, resistance, etc. However, by the arrangement shown the current value through the rimary P of the transformer may be varie within any range from practically no current to full current value. The adjustable inductance L may be em loyedto determine the value of the current owing in the primary P when the key I: is open. A resistance may be used in its stead, or it may be omitted alto ether.

In Fig. 2 the primary P of the translormer is again shown in circuit with the source G, but the secondary and the oscillating circuit, aerial conductor, etc;, are omitted. Here, there are continuousl in circuit with the primary'P and in par el with each other the inductive windi L and L associated res ectiveliy with lli e ad'ustable cores 3 and An associated wit the winding L. and 110 the core 0, and differential with respect to the coil L, is the inductive coil or winding L. And, similarly, there is associated with the core C and the inductive winding L the inductive winding L in differential relation with respect to the coil L". All these windings are adjustable as shown, and as described in connection with Fig. 1. The coils L and L are thrown into parallel with the coils L and L respectively when the member D, connected with one terminal of the source G, is ulled downwardl into enga ement with t e contacts a and forming t e terminals respectively of the windings L and L. The member Dis operated by the relay or other magnets M whose armature F is connected to the member D, the magnets M beingenergized by current from the battery or ot er source B, under the control of the ke k, a switch or other device 0 being include in the ke circuit. When the key 7 k is depresse the electromagnets 'M are energized and attract the armature F causing the member D to engage the contacts a and I) thus throwing the coils L and L into paralle with the coils L and L respectively. Thus, some current is flowing through the primary P at all times, but upon the depression of the key, far greater current flows through the primary In the cases of both Figs. 1 and 2 the current normally flowing throu h the primary P isinsufl'icient to cause spa ring at the gap 8, but when the key is depressed the current through the primary is greatly increased and 18 not only sufficient to cause sparking at the gap :1 but suflicient to send a very powerful s1 y the arrangements above described, great amounts of energy may be easily hanled by a simple key without danger to the key ints or contacts and without serious sparfimg pairs of differential coils are shown in arallei with each other and in series with t e primary P, it is to be understood that more pairs may be so used either in parallel, or in series, orm other relation.

While in Fig. 2 two contactsia and b are engaged to exercise the control, such contacts may be engaged by the member D either simultaneously or non-simultaneously.

By the arrangements herein shown and described, the primary current is kc t below the value required for sparking at t e spark ap, and when the key is pressed there is no oss of energy in the primary circuit since the resistances of the coils are low and when thrown into parallel, the combined resistance is practically zero.

What I claim is: 1. In a transmitter of electro-radiant en: ergy, the combination with a source of energy, of oscillation producing means deriving ctr energy therefrom, difi'erentially related inor arcing. Andwhile in Fig. 2 two ductances associated with said source, and a ke for cutting in and out an inductance of said differentially related inductances.

2. In a transmitter of electro-radiant energy, the combination with a source of energy, of oscillation producing means deriving energ from said source, a lurality of pairs of d erentially related in uctances associated with said source, and a keifor cutting in and out an inductance of eac pair.

3. In a transmitter of electroradiant energy, the combination with a source of energy, of means for producing oscillations deriving ener from said source, differentially related in uctances associated with said source, and a keyforcutting an inductance in and out of parallel relation with a diiierentially related inductance.

4. In a transmitter of electro-radiant energy, the combination with a source of energy, of means for producing oscillations derivihg ener from said source, a plurality of pairs of d erentially related inductances connected in parallel with each other and means for cutting an inductance of each differential pair into and out of parallel relation with its associated inductance.

5. In a transmitter of electro-radiant energy, the combination with a source of current, of means for producin high frequency oscillations deriving energy rom said source, a plurality of inductances associated with said source, and si aling means for renderifplg the effect of said inductances practically ,whereby increased energy is supplied to said oscillation producing means.

6. In telegraphic transmitting ap aratus, the combination with a source 0 fluctuating energy, of differentially related inductances associated with said source, and a key for cuttin in and out an inductance of said difi'erentia y related inductances, said inductances cooperating to increase the transmitted energy.

7. In apparatus for telegraphically transmitting re atively great amounts of energy, the combination with a source of fluctuating ener of differentially. related inductances associated with said source, and a key for outtin in and out aninductance of said difleren: tia y related inductances,said inductances cooperating to increase the transmitted ener 8-. In transmitting apparatus, the com ination with a source of energy, of a plurality of pairs of differentially related inductances associated with said source, and a key for cutting in and out an inductance of each pair.

9. In telegraphic transmittin apparatus, the combination with a source 0 'fluctuating energy, of'difierentially related inductances associated with said source, and a key for cutting in and out an inductance in parallel with a differentially related inductance, said inductances when in parallel increasing the transmitted energy.

10. In apparatus for transmitting electroradiant energy, the combination with a source of energy, of oscillation producing means deriving energy therefrom, difierentially related inductances associated with said source, and a transmitter for controlling an inductance of said difierentially related inductances.

11. In apparatus for transmitting electro radiant energy, the combination with a source of energy, of oscillation producing means deriving energy therefrom, differentially related inductances associated with said source, and a transmitter for controlling said differentially related inductances, the 5 fixed my signature in the oresence of the two 20 subscribing Witnesses. HARRY SHOEMAKER.

W'itnesses:

E. F. DUFFY,

JAMES M. SAWYER. 

